using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Threading;
using System.Windows.Forms;
using SharpDX;
using SharpDX.Direct3D9;
using SharpDX.Mathematics;
using SharpDX.Mathematics.Interop;
using Color = SharpDX.Color;
using Font = SharpDX.Direct3D9.Font;

namespace SoratosExternalWH
{
    public partial class frm_drawing : Form
    {
        private Margins marg;

        //this is used to specify the boundaries of the transparent area
        internal struct Margins
        {
            public int Left, Right, Top, Bottom;
        }

        [DllImport("user32.dll", SetLastError = true)]

        private static extern UInt32 GetWindowLong(IntPtr hWnd, int nIndex);

        [DllImport("user32.dll")]

        static extern int SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        [DllImport("user32.dll")]

        static extern bool SetLayeredWindowAttributes(IntPtr hwnd, uint crKey, byte bAlpha, uint dwFlags);

        public const int GWL_EXSTYLE = -20;

        public const int WS_EX_LAYERED = 0x80000;

        public const int WS_EX_TRANSPARENT = 0x20;

        public const int LWA_ALPHA = 0x2;

        public const int LWA_COLORKEY = 0x1;

        [DllImport("dwmapi.dll")]
        static extern void DwmExtendFrameIntoClientArea(IntPtr hWnd, ref Margins pMargins);

        [StructLayout(LayoutKind.Sequential)]
        public struct RECT
        {
            public int Left;        // x position of upper-left corner
            public int Top;         // y position of upper-left corner
            public int Right;       // x position of lower-right corner
            public int Bottom;      // y position of lower-right corner
        }

        struct FIXED {
            public short fract;
            public short value;
        }

        struct POINTFX {
            public int x;
            public int y;
        }

        [DllImport("user32.dll", SetLastError=true)]
        static extern bool GetWindowRect(IntPtr hwnd, out RECT lpRect);

        [DllImport("user32.dll")]
        static extern bool ClientToScreen(IntPtr hWnd, ref POINTFX lpPoint);

        [DllImport("user32.dll", SetLastError = true)]
        static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

        [DllImport("user32.dll")]
        static extern bool AdjustWindowRectEx(ref RECT lpRect, uint dwStyle,
            bool bMenu, uint dwExStyle);

        enum DWMWINDOWATTRIBUTE : uint
        {
            NCRenderingEnabled = 1,
            NCRenderingPolicy,
            TransitionsForceDisabled,
            AllowNCPaint,
            CaptionButtonBounds,
            NonClientRtlLayout,
            ForceIconicRepresentation,
            Flip3DPolicy,
            ExtendedFrameBounds,
            HasIconicBitmap,
            DisallowPeek,
            ExcludedFromPeek,
            Cloak,
            Cloaked,
            FreezeRepresentation
        }

        [DllImport("dwmapi.dll")]
        static extern int DwmGetWindowAttribute(IntPtr hwnd, DWMWINDOWATTRIBUTE dwAttribute, out RECT pvAttribute, int cbAttribute);

        private Device _device;
        private Font _font;

        private RECT windowBounds;
        public frm_drawing()
        {
            InitializeComponent();
            InitDevice();

            IntPtr csHandle = FindWindow((string)null, "Unbenannt - Editor");

            // if window found
            if (csHandle != IntPtr.Zero)
            {
                Thread renderThread = new Thread(Render) {IsBackground = true};
                renderThread.Start(csHandle);
            }
        }

        private void InitDevice()
        {
            //Make the window's border completely transparant
            SetWindowLong(this.Handle, GWL_EXSTYLE,
                (IntPtr)(GetWindowLong(this.Handle, GWL_EXSTYLE) ^ WS_EX_LAYERED ^ WS_EX_TRANSPARENT));

            //Set the Alpha on the Whole Window to 255 (solid)
            SetLayeredWindowAttributes(this.Handle, 0, 255, LWA_ALPHA);

            PresentParameters pp = new PresentParameters
            {
                Windowed = true,
                SwapEffect = SwapEffect.Discard,
                BackBufferFormat = Format.A8R8G8B8
            };

            _device = new Device(new Direct3D(), 0, DeviceType.Hardware, this.Handle, CreateFlags.HardwareVertexProcessing, pp);
            var fontDescription = new FontDescription
            {
                Height         = 16,
                FaceName       = "Consolas",
                PitchAndFamily = FontPitchAndFamily.Mono,
                Quality        = FontQuality.Draft
            };
            _font = new Font(_device, fontDescription);

        }

        private RECT GetWindowClientArea(IntPtr handle)
        {
            //int size = Marshal.SizeOf(typeof(RECT));
            //DwmGetWindowAttribute(handle, DWMWINDOWATTRIBUTE.ExtendedFrameBounds, out var rect, size);

            /*
            GetWindowRect(handle, out var rect);
            WindowStyles style = WindowStyles.WS_CAPTION | WindowStyles.WS_POPUP | WindowStyles.WS_VISIBLE |
                                 WindowStyles.WS_CLIPSIBLINGS | WindowStyles.WS_SYSMENU | WindowStyles.WS_MINIMIZEBOX;

            WindowStylesEx stylesEx = WindowStylesEx.WS_EX_LEFT | WindowStylesEx.WS_EX_LTRREADING |
                                      WindowStylesEx.WS_EX_RIGHTSCROLLBAR | WindowStylesEx.WS_EX_WINDOWEDGE;

            AdjustWindowRectEx(ref rect, (uint)style, false, (uint)stylesEx);*/

           /* POINTFX pt;
            pt.x = 0;
            pt.y = 0;

            ClientToScreen(handle, ref pt);*/

            /*
            rect.Left = pt.x;
            rect.Right += pt.x;
            rect.Top += pt.y;
            rect.Bottom += pt.y;*/
            GetWindowRect(handle, out var rect);
            return rect;
        }

        private float GetCenterOfScreenX()
        {
            //return (windowBounds.Right / 2) + (windowBounds.Left / 2);
            return windowBounds.Left;
        }

        private float GetCenterOfScreenY()
        {
            //return (windowBounds.Bottom / 2) + (windowBounds.Top / 2);
            return windowBounds.Top;
        }


        private void Render(object windowHandle)
        {
            while (true)
            {
                windowBounds = GetWindowClientArea((IntPtr)windowHandle);
                _device.Clear(ClearFlags.Target, new RawColorBGRA(0,0,0,0), 1.0f, 1);

                /*
                _device.SetRenderState(RenderState.ZEnable, false);
                _device.SetRenderState(RenderState.Lighting, false);
                _device.SetRenderState(RenderState.CullMode, Cull.None);
                _device.SetTransform(TransformState.Projection, Matrix.OrthoOffCenterLH(windowBounds.Left, windowBounds.Right, windowBounds.Bottom, windowBounds.Top, 0, 1));*/

                _device.BeginScene();
/*
                string formatted = $"Left: {windowBounds.Left} Top: {windowBounds.Top} Right: {windowBounds.Right} Bottom: {windowBounds.Bottom} ";
                _font.DrawText(null, formatted, 100, 100, Color.Red);

                _font.DrawText(null, $"Center X: {GetCenterOfScreenX()} Center Y: {GetCenterOfScreenY()}", 100, 120, Color.Red);
*/
                Line crossLine = new Line(_device);
                Vector2[] vecCross1 = {
                    new Vector2(windowBounds.Left, windowBounds.Top),
                    new Vector2(windowBounds.Right, windowBounds.Top)
                };
                Vector2[] vecCross2 = {
                    new Vector2(windowBounds.Left, windowBounds.Top),
                    new Vector2(windowBounds.Left, windowBounds.Bottom)
                };
                /*
                Vector2[] vecCross1 = {
                    new Vector2(GetCenterOfScreenX() - 10, GetCenterOfScreenY()),
                    new Vector2(GetCenterOfScreenX() + 10, GetCenterOfScreenY())
                };
                Vector2[] vecCross2 = {
                    new Vector2(GetCenterOfScreenX(), GetCenterOfScreenY()-10),
                    new Vector2(GetCenterOfScreenX(), GetCenterOfScreenY()+10)
                };*/

                crossLine.Draw(vecCross1, Color.Red);
                crossLine.Draw(vecCross2, Color.Red);
                //crossLine.Draw(vecCross2, Color.Red);

                /*
                Line line = new Line(_device);
                line.GLLines = true;
                line.Antialias = false;
                line.Width = 1;
                Vector2[] vec = {new Vector2(0+windowBounds.Left, 0+windowBounds.Top), new Vector2(100+windowBounds.Left, 100+windowBounds.Top)};
*/

                _device.EndScene();
                _device.Present();
            }
        }

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            marg.Left = 0;
            marg.Top = 0;
            marg.Right = this.Width;
            marg.Bottom = this.Height;

            DwmExtendFrameIntoClientArea(this.Handle, ref marg);
        }
    }
}